We compared coefficient alpha with five alternatives (omega total, omega RT, omega h, GLB, and coefficient H) in two simulation studies. Results showed for unidimensional scales, (a) all indices except omega h performed similarly well for most conditions; (b) alpha is still good; (c) GLB and coefficient H overestimated reliability with small…

Classically parallel, tau-equivalently parallel, and congenerically parallel models representing various degrees of part-test parallelism and their appropriateness for tests composed of multiple item formats are discussed. An appropriate reliability estimate for a test with multiple item formats is presented and illustrated. (SLD)

In low-stakes testing, the motivation levels of examinees are often a matter of concern to test givers because a lack of examinee effort represents a direct threat to the validity of the test data. This study investigated the use of response time to assess the amount of examinee effort received by individual test items. In 2 studies, it was found…